Bar clamps are well known in many applications, including to the construction industry as well as to craftsmen, for use in holding a work piece in a fixed position. Typically, a bar clamp is used to hold multiple objects together for gluing, welding, or other purposes where it is advantageous to temporarily retain the multiple objects comprising the workpiece in a fixed position.
A bar clamp secures workpieces between the clamp's moveable arms. Different size workpieces can be accommodated by adjusting the clamp's jaw members along the length of the bar. A given bar clamp can accommodate workpieces ranging in size from a very small piece when the jaw members are disposed close together, up to a large piece when the jaw members are at opposite ends of the bar. The largest workpiece a bar clamp can accommodate is typically slightly smaller than the length of the bar. Working on projects with greatly varying workpiece sizes requires the purchase of multiple bar clamps since many larger objects will be larger than the operative length of a standard bar clamp, requiring the use of a longer bar clamp. However, overly long bar clamps are more expensive and their use can also be more difficult and/or clumsy than a shorter bar clamp.
The effective use of bar clamps in construction and craft wherein workpieces are of widely varying sizes require the use of multiple bar clamps. Manufacturers must fabricate and then ship the different length bar clamps. Switching manufacturing between different length bar clamps breaks up assembly line production. Shipping the longer bar clamps is inefficient and expensive because of the increased volume of each clamp, raising shipping costs and resulting in the shipment of fewer pieces in each shipping container. Hardware stores must stock larger inventories of bar clamps in order to have at least a few of each size on hand to accommodate the needs of their clientele. Workmen must purchase, and then find a way to transport and store, multiple bar clamps of varying lengths in order to ensure that the proper equipment is on hand at each project.
After the manufacturing cost, typically the single largest cost of getting a good to market is shipping. The more space-efficiently a product can be packed, the greater the savings to the manufacturer, and in turn, the consumer. Similarly, storage space is often a big factor in consumer purchasing decisions. Lengthy and unwieldy bar clamps can result in the use of incorrectly-sized bar clamps or abandonment of a project rather than consumer purchase of an unwieldy and limited-use extra-long bar clamp.